Butte's kin (4)
I believe the answer is:
mesa
'butte's kin' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for mesa that I've seen before include "Flat tableland with steep edges" , "In the US south-west, a steep-sided flat-topped hill" , "Flat hill" , "In the USA, a steep-sided flat-topped hill" , "Flat-topped hill with steep sides, common in the southwestern US" .)